1. Field of the Invention
The present invention generally relates to gunshot detection. More particularly, the present invention is directed to using multiple installations of sound detection an recording devices for detecting firing of a gun or an explosion, identifying of a location of such firing or explosion, and recording images of an area of a source of the firing or explosion and of a possible suspect of such firing or explosion.
2. Description of the Related Art
Violence and criminal activity involving firearms is a significant problem for most metropolitan areas in the United States, and numerous suburban areas as well. Two of the problems facing law enforcement authorities when handling these types of crimes are (1) the speed at which the violence begins and ends and (2) the relative ease and speed at which the perpetrators can disappear into the urban landscape.
At no time have these problems been emphasized more than during the sniper killings of October 2002 in the greater Washington, D.C. area. With killings occurring almost at will, local and federal law enforcement agencies were being constantly stifled by the lack of reliable descriptions of exactly who and what they were looking for.
All law enforcement agencies agree that having reliable, accurate intelligence of who and what took part in a violent crime can enormously enhance their ability to apprehend the perpetrators. Similarly, counter-terrorism efforts of sovereign governments abroad and the Department of Homeland Security would be greatly helped in their fight against organized crime and terrorism if they had at their disposal a network of systems to detect, pinpoint, and record an event e.g., a shooting or an explosion, immediately upon the event occurring, as well as those involved in carrying out the crime.
Presently, technology has no capability to image the origin of a gunshot event immediately upon its detection. Existing technology is only able to report the location of such event. Certain existing infrared (IR) systems can detect a muzzle flash from a gunshot and subsequently localize the presence of the gun. However, these systems are extremely limited, because the imaging system must have the muzzle of the gun being fired in the field of view and much more often than not the muzzle is hidden.
There are also numerous systems that utilize acoustic triangulation technology to locate the origin of gunshot events, these include AAI Corporation's PDCue Counter Sniper Systems, Trilon Technology's Shot Spotter, and Tag-It. Similarly, digital imaging systems are plentiful. There is, however, no known system that integrates the two technologies, i.e., acoustic triangulation, and reporting the location of an event.
Gunshot Range and Direction Detection
Gunshot range and direction indicators have been developed for the military to help in locating snipers. Six different phenomenologies have been exploited in developing different systems to accomplish this task: (1) muzzle blast; (2) bullet shockwave; (3) muzzle flash; (4) bullet-in-flight heat signature; (5) optical laser reflection; and (6) vortex gradients in atmospheric refractive index.
However, all but one of the most promising of these phenomenologies are contingent on aspects of the military application that are different from the civilian law enforcement/Homeland Security application. In the military environment, gunshots are being aimed in the general direction of the friendly forces, and hence in the general direction of the detection system itself. The law enforcement application cannot make a determination of the direction of the criminal perpetrator's actions before the event, and hence there exists a need for a system designed for near omni-directional detection and image gathering.
In the urban setting, the range and direction of the gunshot can only be determined reliably by triangulating the acoustic sound wave produced by the firearm's muzzle blast. Current versions of these types of systems use acoustic sensors separated by sufficient distances so as to enable accurate calculations. Upon each sensor detecting the gunshot's sound wave, a computing device records the times of sound arrival and subsequently triangulates the source location and direction of the sound. Initial testing of current systems by the companies developing them, has indicated that accurate responses at the desired range, e.g., about one kilometer, are feasible, although the accuracy is heavily conditioned on sensor separation.
It would therefore be desirable to provide a system to detect a gunshot, determine the direction from which it was fired, identify the ground zero location of the gunshot event, and initiate recording of the area of the event immediately upon the event occurring.